Controlling communications between visible light communication access points and user equipments

ABSTRACT

A coordination node can be configured to control communications between Visible Light Communication, VLC, Access Points, APs, and user equipments, UEs. The coordination node can: identify occurrence of an event relating to operation of a first VLC AP; determine that a second VLC AP and a third VLC AP each have communication coverage areas that are at least partially within a communication coverage area of the first VLC AP; control the second VLC AP to avoid it interfering with communications between the first VLC AP and a UE while it is within a common communication coverage area of the first VLC AP and the second VLC AP; and control the third VLC AP to avoid it interfering with communications between the first VLC AP and the UE while it is within a common communication coverage area of the first VLC AP and the second VLC AP.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/313,085 titled “Controlling Communications Between Visible LightCommunication Access Points and User Equipments” filed on Dec. 24, 2018,which is a 35 U.S.C. § 371 national stage application of PCTInternational Application No. PCT/EP2016/065261, filed on Jun. 30, 2016,the disclosure and content of which are incorporated by reference hereinin their entireties.

TECHNICAL FIELD

The present disclosure relates generally to networking systems andmethods and more particularly to Visible Light Communication (VLC)systems and related Access Points (AP).

BACKGROUND

With the explosion of smart phones, tablets, laptops, and other userequipment (UE) both in enterprise (e.g., bring your own device or BYOD)and guest account scenarios, there is an ever increasing demand forwireless bandwidth in high density UE environments. Conventionally, WLAN(also referred to as Wireless Fidelity (WiFi)) is a primary means ofconnectivity for UEs. WLAN is generally defined in IEEE 802.11 andvariants thereof. The wireless spectrum which is necessary forcommunication between WiFi/WLAN Access Points (APs) and UEs is becomingincreasingly scarce as demand grows exponentially with the proliferationof such devices.

Deploying more WiFi/WLAN Access Points (APs) may not be a right solutionbecause of already high levels of interference from competing devices.Many UEs support communication modes beyond WiFi, including utilizingsubscriber services provided by wireless service operators with 3G, 4GLong Term Evolution (LTE), and other communication protocols.Disadvantageously, connectivity through subscriber services can be morecostly and/or may provide lower bandwidth than WiFi. Accordingly, thereis a need for alternative systems and methods to providing wirelessbandwidth in high density UE environments.

Visible Light Communication (VLC) systems use the visible light portionof the electromagnetic spectrum for communication between APs and UEs.VLC may also be referred to as LiFi (Light WiFi). VLC is an alternativeto a radio frequency based communications approach but can also be proneto interference in some environments.

SUMMARY

Some embodiments disclosed herein are directed to a method by acoordination node for controlling communications between Visible LightCommunication, VLC, Access Points, APs, and user equipments, UEs. Themethod includes identifying occurrence of an event relating to operationof a first VLC AP. The method further includes, responsive toidentifying the occurrence of the event, determining that a second VLCAP and a third VLC AP each have communication coverage areas that are atleast partially within a communication coverage area of the first VLCAP. The method further includes, responsive to identifying theoccurrence of the event, controlling the second VLC AP to avoid itinterfering with communications between the first VLC AP and a UE whileit is within a common communication coverage area of the first VLC APand the second VLC AP. The method further includes, responsive toidentifying the occurrence of the event, controlling the third VLC AP toavoid it interfering with communications between the first VLC AP andthe UE while it is within a common communication coverage area of thefirst VLC AP and the second VLC AP.

A potential advantage of this approach is that it can provide moreefficient and robust management of VLC APs that have commoncommunication coverage areas. When a VLC AP having a larger coveragearea that overlaps smaller areas of two other VLC APs, occurrence of adefined event can trigger the VLC APs to be controlled so that thelarger area VLC AP takes over for the smaller area VLC APs for handlingcommunications with the UEs. Potential interference is thereby avoidedand mobility of those UEs is enhanced. Moreover, replacing operation ofthe smaller coverage area VLC APs with the larger area single VLC AP canprovide power savings during the continuing communications with the UEs.Various events that can trigger the transfer of control can includepower-on of the larger area VLC AP, power-off of one or both of thesmaller area VLC APs, loss of ability of one or both of the smaller areaVLC APs to communicate with UEs, etc. Passing communicationresponsibility from the larger area VLC AP to the smaller area VLC APscan also occur responsive to defined events.

Some other related embodiments are directed to a coordination node forcontrolling communications between Visible Light Communication, VLC,Access Points, APs, and user equipments, UEs. The coordination node caninclude a network interface; a processor coupled to the networkinterface; and a memory coupled to the processor and storing programcode that when executed by the processor causes the processor to performoperations. The operations include identifying occurrence of an eventrelating to operation of a first VLC AP. The operations further include,responsive to identifying the occurrence of the event, determining thata second VLC AP has a communication coverage area that is at leastpartially within a communication coverage area of the first VLC AP. Theoperations further include, responsive to determining that the secondVLC AP has a communication coverage area that is at least partiallywithin a communication coverage area of the first VLC AP, controllingthe second VLC AP, separate from handling over a UE between the firstVLC AP and the second VLC AP, to avoid the second VLC AP frominterfering with communications between the first VLC AP and any UEswithin a common communication coverage area of the second VLC AP and thefirst VLC AP.

Other methods, coordination nodes, computer program products, andsystems according to embodiments will be or become apparent to one withskill in the art upon review of the following drawings and detaileddescription. It is intended that all such additional methods,coordination nodes, computer program products, and systems be includedwithin this description and protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are illustrated by way of example andare not limited by the accompanying drawings. In the drawings:

FIG. 1 is a block diagram of a system that includes a coordination nodethat controls communications between VLC APs and UEs in accordance withsome embodiments of the present disclosure;

FIG. 2 is a combined data flow diagram and flowchart of operations by acoordination node, VLC APs and UEs in accordance with some embodimentsof the present disclosure;

FIGS. 3-11 are flowcharts of operations and methods by a coordinationnode to control communications between VLC APs and UEs in accordancewith some embodiments of the present disclosure;

FIG. 12 is a block diagram of a coordination node that is configuredaccording to some embodiments of the present disclosure;

FIG. 13 is a block diagram of modules forming a coordination node thatis configured according to some embodiments of the present disclosure;and

FIG. 14 is a block diagram of a VLC AP that is configured according tosome embodiments of the present disclosure.

DETAILED DESCRIPTION

Inventive concepts will now be described more fully hereinafter withreference to the accompanying drawings, in which examples of embodimentsof inventive concepts are shown. Inventive concepts may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein. Rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of various present inventive concepts to thoseskilled in the art. It should also be noted that these embodiments arenot mutually exclusive. Components from one embodiment may be tacitlyassumed to be present/used in another embodiment.

Embodiments of the present disclosure are directed to improving howcommunications between VLC APs and UEs are controlled when the VLC APshave at least partially overlapping communication coverage areas.Although the light sources used for VLC APs can have light beamsconfigured to provide more well defined communication coverage areasthan RF based APs, VLC APs can have overlapping communication coverageareas that can be a source of interference to each other. Moreover,solid or opaque objects within the communication coverage areas caninterfere with VLC coverage and generate interference in ways that don'toccur with RF based communications. VLC APs are also anticipated to beused predominately indoors where their density and associatedcommunication coverage areas can overlap in complex ways and wheremobility of UEs, such as while a user is walking down a hallway, cancomplicate the ability of such systems to maintain reliablecommunication links.

FIG. 1 is a block diagram of a system that includes a coordination node110 that controls communications between VLC APs 130 and UEs 108 inaccordance with some embodiments of the present disclosure. The VLC APs130 are connected to a wide area network (WAN) 150 through a local areanetwork (LAN) switch 140 via, e.g., a power line network through theirpower line connections, WiFi, or other wired/wireless connection. TheVLC APs 130 each have a communication coverage area in which they usethe visible light portion of the electromagnetic spectrum forcommunicating data from/to UEs 108 and the LAN switch 140.

In the non-limiting example of FIG. 1, a first VLC AP 130 controls(modulates) a first light source 100, e.g., ceiling mounted light, totransmit data toward UEs 108 and receive data from the UEs 108 within acommunication coverage area of the first light source 100 and anassociated light receiver. A second VLC AP 130 communicates with UE_A108 through a smaller communication coverage area provided by a secondlight source 102, e.g., floor lamp, and an associated light receiver.Similarly, a third VLC AP 130 communicates with UE_B 108 through asmaller communication coverage area provided by a third light source104, e.g., floor lamp, and a receiver. A fourth VLC AP 130 communicateswith any UEs in the communication coverage area of a fourth light source106, e.g., a table lamp, and associated light receiver.

The communication coverage area of the first VLC AP 130 is illustratedin FIG. 1 as overlapping the communication coverage areas of the secondand third VLC APs 130. The fourth VLC AP 130 is illustrated as having anon-overlapping coverage area with the second and third VLC APs 130. Thefirst VLC AP 130 may provide communication coverage underneath the tableon which the fourth light source rests.

Potential problems that can arise with the illustrated system includethat the overlapping communication overage areas of at least the first,second, and third VLC APs 130 can interfere with each other'scommunications with UEs 108. In accordance with some embodiments, thecoordination node 110 controls communications by the VLC APs 130responsive to identifying occurrence of one or more defined eventsrelating to operation of one or more of the VLC APs 130. Althoughvarious embodiments are described in the context of events relating tothe VLC APs 130, it is to be understood that this description means alsoevents that can be associated with the light sources and/or lightreceivers controlled by the VLC APs 130, such when as a light sourcebecomes powered-on, powered-off, inoperative to emit light, inoperativeto receive light, etc.

FIG. 2 is a combined data flow diagram and flowchart of operations bythe coordination node 110, the VLC APs 130, and the UEs 108 inaccordance with some embodiments of the present disclosure.

Referring to FIGS. 1 and 2, UE_A communicates 200 with the second VLC AP130 controlling the second light source 102 to receive and transmitdata, and UE_B communicates 202 with the third VLC AP 130 controllingthe third light source 104 to receive and transmit data. A defined eventsubsequently occurs (block 204) affecting operation of the first VLC AP130. The defined event may correspond to the first VLC AP 130 beingturned ON or the first light source 100 being turned ON. Thus, in oneembodiment an event associated with operation of the first VLC AP 130can be an event that directly affects operability of the first VLC AP130 or an event that affects operability of the first light source 100controlled by the first VLC AP 130 and which, thereby, indirectlyaffects operability of the first VLC AP 130. Because the first, second,and third light sources 100-104 have at least partially overlappingcommunication coverage areas, the first light source 100 could interferewith the communications 200 and 202 with UE_A and UE_B, respectively,and any other UEs in those coverage areas.

In one embodiment, the coordination node 110 identifies (block 206)occurrence of the event relating to operation of the first VLC AP 130.Responsive to identification of occurrence of the event, thecoordination node 110 determines (block 208) that the second VLC AP 130and the third VLC AP 130 each have communication coverage areas that areat least partially within the communication coverage area of the firstVLC AP 130. The coordination node 110 determines (block 210) aresponsive action to be performed based on the determined topology. Theresponsive action triggers the coordination node 110 to control (block212) the second and the third VLC APs 130 responsively to avoid theirinterfering with communications between the first VLC AP 130 and any UEs108 within common communication coverage areas of the second or thethird VLC APs 130. The control (block 212) may include transmitting amessage (214) to the second VLC AP 130 to disable its AP operation(e.g., turn-off the second light source 102 or disable its VLCmodulation of light emitted therefrom), and similarly transmitting amessage (216) to the third VLC AP 130 to disable its AP operation (e.g.,turn-off the third light source 104 or disable its VLC modulation oflight emitted therefrom). The coordination node 110 may communicate asingle message instead of separate messages 214 and 216 toward thesecond and third VLC APs 130, respectively. When the event that isidentified (block 206) affects operability of the first light source 100(e.g., turned ON), the coordination node 110 can send a message to thefirst VLC AP 130 commanding it to turn ON or otherwise become operableto perform VLC through the first light source 100.

UE_A and UE_B may then continue to receive and transmit data 218 and 220through the first VLC AP 130. The operations may be performed so thatcommunications between the UEs 108 and the LAN switch 140 are notinterrupted by the disabling of AP operation of the second and third VLCAPs 130.

A potential advantage of this approach is that it can provide moreefficient and robust management of the VLC APs. Potential interferencebetween the first VLC AP 130 and the pair of second and third VLC APs130 is avoided and mobility of the UEs 108 is enhanced. Moreover,replacing operation of the second and third VLC APs 130 with the largerarea first VLC AP 130 can provide power savings for the continuingcommunications with the UEs 108.

To determine (block 208) which VLC APs 130 have overlappingcommunication coverage areas, the coordination node 110 may access a VLCAP coverage area topology repository 120 that contains topologyinformation identifying which VLC APs 130 have at least partiallyoverlapping communication coverage areas.

In one embodiment the topology information is defined by an operatorwhen the light sources 100, 102, 104, and 106 are installed or placedwithin a room, by observing and recording which of the light sources 100have overlapping illuminated areas. In another embodiment the topologyinformation is determined by the coordination node 110 based on reportsreceived from the VLC APs 130 which indicate which VLC APs 130 havedetected in their respective coverage areas signals transmitting byother adjacent VLC APs 130.

In yet another embodiment the topology information is determined by thecoordination node 110 based on coverage reports that are transmitted bythe UEs 108 through their servicing VLC APs 130 which indicate fromwhich VLC APs 130 the respective UEs 108 have received signals. Thus,for example, when a UE coverage report from UE_A 108 indicates that ithas received signals from the first VLC AP 130 and from the second VLCAP 130, the coordination node 110 determines that the first and secondVLC APs 130 have at least partially overlapping coverage areas andresponsively updates topology information in the VLC AP coverage areatopology repository 120. The coordination node 110 can similarly updatethe topology information in the VLC AP coverage area topology repository120 to indicate that the first and third VLC APs 130 have at leastpartially overlapping coverage areas responsive to a UE coverage reportfrom UE_B 108 indicating that it has received signals from the first VLCAP 130 and from the third VLC AP 130. In this manner the coordinationnode 110 can learn over time and update the VLC AP coverage areatopology repository 120 to indicate which VLC APs have at leastpartially overlapping communication coverage areas.

Further embodiments are now explained in the context of FIGS. 3-11,which are flowcharts of operations and methods by the coordination node110 to control communications between the VLC APs 130 and UEs 108.

In some embodiments, the coordination node 110 disables operation of thesecond and third VLC APs 130 responsive to identifying that the firstVLC AP 130 has become powered-on. Referring to FIG. 3, the coordinationnode 110 identifies (block 300) that the first VLC AP 130 hastransitioned to a power-on state, such as due to a user operating a wallmounted power-switch, or occurrence of another defined event relating tooperation of the first VLC AP 130. A determination (block 302) is madethat the second VLC AP 130 and the third VLC AP 130 each havecommunication coverage areas that are at least partially within thecommunication coverage area of the first VLC AP 130, responsive toidentification of occurrence of the event. The coordination node 110communicates (block 304) toward the second VLC AP 130 a messagecontaining a power-off command, and communicates (block 306) toward thethird VLC AP 130 a message containing a power-off command. Thecoordination node 110 may communicate a single message instead ofseparate messages toward the second and third VLC APs 130.

The coordination node 110 may additionally or alternatively initiatere-routing of data packets responsive to identifying occurrence of anevent relating to operation of the first VLC AP 130, such as an eventindicating that the first VLC AP 130 has transitioned to a state thatnow allows it to perform VLC with UEs. Referring to FIG. 4, thecoordination node 110 identifies (block 400) occurrence of an eventrelating to operation of the first VLC AP 130, and responsivelydetermines (block 402) that the second VLC AP 130 and the third VLC AP130 each have communication coverage areas that are at least partiallywithin a communication coverage area of the first VLC AP 130. Theidentified event may correspond to the first VLC AP 130 becomingpowered-on or otherwise becoming able to communicate with UEs 108. Thecoordination node 110 responsively initiates (block 404) re-routing ofdata packets, which are addressed to a UE within the communicationcoverage area of the second VLC AP 130, to be directed to the first VLCAP 130 instead of to the second VLC AP 130, and initiates (block 406)re-routing of data packets, which are addressed to the UE_B 108 withinthe communication coverage area of the third VLC AP 130, to be directedto the first VLC AP 130 instead of to the third VLC AP 130. Thecoordination node 110 may furthermore control the second and third VLCAPs 130 to turn off the second and third light sources 102 and 104,respectively, or otherwise disable their modulation of light emittedtherefrom so as to avoid interfering with VLC between the first VLC AP130 and UEs 108.

The coordination node 110 may subsequently control the second and thirdVLC APs 130 to restore their communications with UEs responsive todetecting occurrence of an event associated with loss of the ability ofthe first VLC AP 130 to communicate with the UEs, e.g., power-off oroperational failure of the first VLC AP 130 and/or the first lightsource 100. Referring to FIG. 5, the coordination of 110 identifies(block 500) loss of ability of the first VLC AP 130 to communicate withUEs 108 and, responsively controls (block 502) the second and the thirdVLC APs 130 to restore their operations to communicate with UEs 108,e.g., UE_A and UE_B.

In another embodiment, the coordination node 110 operates to control oneor more frequency bands that are used for VLC by the first VLC AP 130and/or by the second and third VLC APs 130 responsive to detecting anevent indicating that interference between the VLC APs 130 could occur.Referring to FIG. 6, the coordination node 110 controls (block 600) thesecond and the third VLC APs 130 to prevent use of at least one lightfrequency band by the first VLC AP 130 for VLC with UEs 108 subsequentto the occurrence of the event.

Although various embodiments have been explained in which thecoordination node 110 directly controls operation of the second andthird VLC APs 130, in some other embodiments the coordination node 110operates to coordinate negotiations between the VLC APs 130 to avoidtheir interfering with each other. Accordingly, decentralizeddecision-making can be performed instead of via centralized decisions bythe coordination node 110. In one embodiment, responsive to thedetermination (e.g., block 208 of FIG. 2 or block 302 of FIG. 3), thecoordination node 110 operates to coordinate negotiations between theVLC APs 130, e.g., first, second, and third VLC APs, for which of theVLC APs 130 will operate to communicate with any UEs in their respectivecoverage areas to avoid their interfering with VLC by other operatingVLC APs. Thus, for example, the coordination node 110 can operate toidentify the overlapping communication coverage areas and initiatenegotiations to occur between the first VLC AP and the second and thirdVLC APs. The negotiations may be performed using negotiation messagingthat is routed through the coordination node 110 and/or directly betweenthe VLC APs 130.

Some other embodiments are directed to operations and methods fordetermining the topology of the communication coverage areas provided bythe plurality of VLC APs 130 and, particularly, recording in therepository 120 which two or more of the VLC APs 130 have at leastpartially overlapping communication coverage areas. In one embodiment,the coordination node 110 determines (block 208, FIG. 2) that the secondVLC AP 130 and the third VLC AP 130 each have communication coverageareas that are at least partially within a communication coverage areaof the first VLC AP 130, based on accessing the coverage area topologyrepository 120 using an identifier for the first VLC AP 130 to obtain anidentifier for the second VLC AP 130 and an identifier for the third VLCAP 130. As explained above, the coverage area topology repository 120maps identifiers for minor VLC APs 130 to identifiers for major VLC APs130, e.g., the first VLC AP, that at least partially overlap smallercommunication coverage areas of the mapped ones of the minor VLC APs130, e.g., the second and third VLC APs 130.

FIG. 7 illustrates example operations and methods that may be performedby the coordination node 110 to add, remove, or modify topologyinformation in the VLC AP coverage area topology repository 120.Referring to FIG. 7, the coordination node 110 receives (block 700)coverage reports from the minor VLC APs 130, e.g., second, third, andfourth VLC APs. Each of the coverage reports contains an identifier forone of the minor VLC APs 130 that sent the coverage report and containsan identifier for one of the major VLC APs 130, e.g., first VLC AP, thatwas received by the one of the minor VLC APs 130 in a data packettransmitted using VLC by the one of the major VLC APs 130.

The coordination node 110 may furthermore respond thereto by determining(block 702) that the communication coverage area of the first VLC AP 130at least partially overlaps the communication coverage area of thesecond VLC AP 130 based on the coverage report received from the secondVLC AP 130 containing the identifier of the first VLC AP 130 and theidentifier of the second VLC AP 130, and then store (block 706) in thecoverage area topology repository 120 the identifier for the first VLCAP 130 with an indicated association to the identifier for the secondVLC AP 130. Similarly, the coordination node 110 can determine (block704) that the communication coverage area of the first VLC AP 130 atleast partially overlaps the communication coverage area of the thirdVLC AP 130 based on the coverage report received from the third VLC AP130 containing the identifier of the first VLC AP 130 and the identifierof the third VLC AP 130, and then store (block 706) in the coverage areatopology repository 120 information associating the identifier for thefirst VLC AP 130 to the identifier for the third VLC AP 130.

Some other embodiments of the disclosure are directed to various eventsthat can trigger the coordination node 110 to control communications byone or more of the VLC APs 130.

In the embodiment of FIG. 8, error rates being experienced by the UEs108 can cause the coordination node 110 to control one or more of theVLC APs 130. More particularly, the coordination node 110 receives(block 800) error rate reports indicating communication error ratesbeing experienced by UEs 108, and selects (block 802) between using thefirst VLC AP 130 or using the second and the third VLC APs 130 tocommunicate with the UEs 108 based on content of the error rate reports.The coordination node 110 controls (block 804) the first, the second,and third VLC APs 130 responsive to the selection (block 802). Thus, forexample, when an excessive error rate occurs in communications betweenthe second VLC AP 130 and UE_A 108, the first VLC AP 130 can beactivated to takeover communication responsibility from the second andthird VLC APs 130.

In the embodiment of FIG. 9, the confidentiality level of informationcontained in packets communicated to UEs can cause the coordination node110 to control one or more of the VLC APs 130. More particularly, thecoordination node 110 determines (block 900) a confidentiality level ofinformation contained in packets being communicated to UEs 108, andselects (block 102) between using the first VLC AP 130 or using thesecond and the third VLC APs 130 to communicate with the UEs 108 basedon the determined confidentiality level of information. The coordinationnode 110 controls (block 904) the first, the second, and the third VLCAPs 130 responsive to the selection (block 902). For example, lessconfidential information can be communicated through the first VLC AP130 to UE_A while highly confidential information (e.g., informationhaving at least a threshold level of secrecy) can be communicationthrough the second VLC AP 130 to UE_A. Using a smaller communicationcoverage area to transmit or receive highly confidential information canreduce the likelihood of it being overheard by other UEs, relative to ifthe larger coverage area of the first VLC AP 130 were instead used.

In the embodiment of FIG. 10, communication bandwidth utilization of thePLC APs 130 can cause the coordination node 110 to control one or moreof the VLC APs 130. More particularly, the coordination node 110determines (block 1000) communication bandwidth utilization of the VLCAPs 130 communicating with UEs 108, and selects (block 1002) betweenusing the first VLC AP 130 or using the second and the third VLC APs 130to communicate with the UEs 108 based on the determined communicationbandwidth utilization. The coordination node 110 controls (block 1004)the first, the second, and the third VLC APs 130 responsive to theselection (block 1002). For example, when the first VLC AP 130 becomesoverloaded by having an excessively high communication bandwidthutilization, the coordination node 110 can trigger the second and thirdVLC APs 130 to takeover communication responsibility from the first VLCAP 130. The smaller communication coverage areas of the second and thirdVLC APs 130 can provider higher bandwidth communications in high densityUE environments compared to the larger communication coverage area ofthe first VLC AP 130.

In the embodiment of FIG. 11, the identifier communication capabilitiesof receiver circuits contained in the VLC APs 130 can cause thecoordination node 110 to control one or more of the VLC APs 130. Moreparticularly, the coordination node 110 determines (block 1100)communication capabilities of receiver circuits contained in the VLC APs108, and selects (block 1102) between using the first VLC AP 130 orusing the second and the third VLC APs 130 to communicate with the UEs108 based on the determined communication capabilities. The coordinationnode 110 controls (block 1104) the first, the second, and the third VLCAPs 130 responsive to the selection (block 1102). For example, themodulation and/or coding capability of the receiver circuits can be usedto select between the VLC APs 130 to provide an improved operationalmatch to the transmitter circuits of UEs that are to be providedservice.

FIG. 12 is a block diagram of the coordination node 110 that isconfigured according to some embodiments of the present disclosure. Thecoordination node 110 includes a processor 1200, a memory 1210, and anetwork interface circuit which may include a radio and/or VLC networktransceiver circuit 1226 and/or a wired network interface 1224 (e.g.,Ethernet interface). The radio and/or VLC network transceiver circuit1226 can include, but is not limited to, a LiFi, a LTE or other cellulartransceiver, WIFI transceiver (IEEE 802.11), Bluetooth, WiMaxtransceiver, or other wireless communication transceiver configured tocommunicate with the VLC APs 130.

The processor 1200 may include one or more data processing circuits,such as a general purpose and/or special purpose processor (e.g.,microprocessor and/or digital signal processor) that may be collocatedor distributed across one or more networks. The processor 1200 isconfigured to execute computer program code 1212 in the memory 1210,described below as a non-transitory computer readable medium, to performat least some of the operations described herein as being performed by acoordination node. The memory 1210 may further include the coverage areatopology repository 120. The coordination node 110 may further include auser input interface 1220 (e.g., touch screen, keyboard, keypad, etc.)and a display device 1222.

FIG. 13 is a block diagram of modules 1300 forming a coordination nodethat is configured according to some embodiments of the presentdisclosure. Referring to FIG. 13, the modules 1300 include an eventoccurrence identifying module 1300, a VLC AP coverage area topologydetermining module 1302, and a VLC AP controlling module 1304. The eventoccurrence identifying module 1300 is for identifying occurrence of anevent relating to operation of a first VLC AP 130. The VLC AP coveragearea topology determining module 1302 is for determining that a secondVLC AP 130 and a third VLC AP 130 each have communication coverage areasthat are at least partially within a communication coverage area of thefirst VLC AP 130, responsive to identification of occurrence of theevent. The VLC AP controlling module 1304 is for controlling the secondand the third VLC APs 130 responsive to the determination to avoid theirinterfering with communications between the first VLC AP 130 and any UEs108 within common communication coverage areas of the second or thethird VLC APs 130.

FIG. 14 is a block diagram of a VLC AP 130 that is configured accordingto some embodiments of the present disclosure. The VLC AP 130 includes aprocessor 1400, a memory 1410, a VLC transceiver circuit 1420, and mayfurther include a wired network interface 1422 (e.g., Ethernet) and/or aradio network transceiver circuit 1424. The VLC transceiver circuit 1420is configured to communicate with UEs 108 according to or moreembodiments herein. The radio network transceiver circuit 1424 caninclude, but is not limited to, a LTE or other cellular transceiver,WIFI transceiver (IEEE 802.11), Bluetooth, WiMax transceiver, or otherwireless communication transceiver configured to communicate with thecoordination node 110.

The processor 1400 may include one or more data processing circuits,such as a general purpose and/or special purpose processor (e.g.,microprocessor and/or digital signal processor) that may be collocatedor distributed across one or more networks. The processor 1400 isconfigured to execute computer program code 1412 in the memory 1210,described below as a non-transitory computer readable medium, to performat least some of the operations described herein as being performed by aVLC AP.

Further Definitions and Embodiments

In the above-description of various embodiments of present inventiveconcepts, it is to be understood that the terminology used herein is forthe purpose of describing particular embodiments only and is notintended to be limiting of present inventive concepts. Unless otherwisedefined, all terms (including technical and scientific terms) usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which present inventive concepts belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of this specification andthe relevant art and will not be interpreted in an idealized or overlyformal sense expressly so defined herein.

When an element is referred to as being “connected”, “coupled”,“responsive”, or variants thereof to another element, it can be directlyconnected, coupled, or responsive to the other element or interveningelements may be present. In contrast, when an element is referred to asbeing “directly connected”, “directly coupled”, “directly responsive”,or variants thereof to another element, there are no interveningelements present. Like numbers refer to like elements throughout.Furthermore, “coupled”, “connected”, “responsive”, or variants thereofas used herein may include wirelessly coupled, connected, or responsive.As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Well-known functions or constructions may not be described indetail for brevity and/or clarity. The term “and/or” includes any andall combinations of one or more of the associated listed items.

It will be understood that although the terms first, second, third, etc.may be used herein to describe various elements/operations, theseelements/operations should not be limited by these terms. These termsare only used to distinguish one element/operation from anotherelement/operation. Thus a first element/operation in some embodimentscould be termed a second element/operation in other embodiments withoutdeparting from the teachings of present inventive concepts. The samereference numerals or the same reference designators denote the same orsimilar elements throughout the specification.

As used herein, the terms “comprise”, “comprising”, “comprises”,“include”, “including”, “includes”, “have”, “has”, “having”, or variantsthereof are open-ended, and include one or more stated features,integers, elements, steps, components or functions but does not precludethe presence or addition of one or more other features, integers,elements, steps, components, functions or groups thereof. Furthermore,as used herein, the common abbreviation “e.g.”, which derives from theLatin phrase “exempli gratia,” may be used to introduce or specify ageneral example or examples of a previously mentioned item, and is notintended to be limiting of such item. The common abbreviation “i.e.”,which derives from the Latin phrase “id est,” may be used to specify aparticular item from a more general recitation.

Example embodiments are described herein with reference to blockdiagrams and/or flowchart illustrations of computer-implemented methods,apparatus (systems and/or devices) and/or computer program products. Itis understood that a block of the block diagrams and/or flowchartillustrations, and combinations of blocks in the block diagrams and/orflowchart illustrations, can be implemented by computer programinstructions that are performed by one or more computer circuits. Thesecomputer program instructions may be provided to a processor circuit ofa general purpose computer circuit, special purpose computer circuit,and/or other programmable data processing circuit to produce a machine,such that the instructions, which execute via the processor of thecomputer and/or other programmable data processing apparatus, transformand control transistors, values stored in memory locations, and otherhardware components within such circuitry to implement thefunctions/acts specified in the block diagrams and/or flowchart block orblocks, and thereby create means (functionality) and/or structure forimplementing the functions/acts specified in the block diagrams and/orflowchart block(s).

These computer program instructions may also be stored in a tangiblecomputer-readable medium that can direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer-readablemedium produce an article of manufacture including instructions whichimplement the functions/acts specified in the block diagrams and/orflowchart block or blocks. Accordingly, embodiments of present inventiveconcepts may be embodied in hardware and/or in software (includingfirmware, resident software, micro-code, etc.) that runs on a processorsuch as a digital signal processor, which may collectively be referredto as “circuitry,” “a module” or variants thereof.

It should also be noted that in some alternate implementations, thefunctions/acts noted in the blocks may occur out of the order noted inthe flowcharts. For example, two blocks shown in succession may in factbe executed substantially concurrently or the blocks may sometimes beexecuted in the reverse order, depending upon the functionality/actsinvolved. Moreover, the functionality of a given block of the flowchartsand/or block diagrams may be separated into multiple blocks and/or thefunctionality of two or more blocks of the flowcharts and/or blockdiagrams may be at least partially integrated. Finally, other blocks maybe added/inserted between the blocks that are illustrated, and/orblocks/operations may be omitted without departing from the scope ofinventive concepts. Moreover, although some of the diagrams includearrows on communication paths to show a primary direction ofcommunication, it is to be understood that communication may occur inthe opposite direction to the depicted arrows.

Many variations and modifications can be made to the embodiments withoutsubstantially departing from the principles of the present inventiveconcepts. All such variations and modifications are intended to beincluded herein within the scope of present inventive concepts.Accordingly, the above disclosed subject matter is to be consideredillustrative, and not restrictive, and the appended examples ofembodiments are intended to cover all such modifications, enhancements,and other embodiments, which fall within the spirit and scope of presentinventive concepts. Thus, to the maximum extent allowed by law, thescope of present inventive concepts are to be determined by the broadestpermissible interpretation of the present disclosure including thefollowing examples of embodiments and their equivalents, and shall notbe restricted or limited by the foregoing detailed description.

1. A method by a coordination node for controlling communicationsbetween Visible Light Communication, VLC, Access Points, APs, and userequipments, UEs, the method comprising: identifying occurrence of anevent relating to operation of a first VLC AP; responsive to identifyingthe occurrence of the event, determining that a second VLC AP and athird VLC AP each have communication coverage areas that are at leastpartially within a communication coverage area of the first VLC AP; andresponsive to identifying the occurrence of the event, controlling thesecond VLC AP to avoid it interfering with communications between thefirst VLC AP and a UE while it is within a common communication coveragearea of the first VLC AP and the second VLC AP; and responsive toidentifying the occurrence of the event, controlling the third VLC AP toavoid it interfering with communications between the first VLC AP andthe UE while it is within a common communication coverage area of thefirst VLC AP and the second VLC AP.
 2. The method of claim 1, whereinidentifying the occurrence of the event relating to operation of thefirst VLC AP comprises identifying that the first VLC AP has becomeoperational to communicate with UEs located within at least part of thecommunication coverage areas of the second VLC AP and the third VLC AP,and wherein controlling the second VLC AP and the third VLC AP comprisesdisabling operation of the second VLC AP and the third VLC AP tocommunicate with UEs.
 3. The method of claim 2, wherein identifying thatthe first VLC AP has now become operational to communicate with UEslocated within the communication coverage areas of the second VLC AP andthe third VLC AP comprises identifying that the first VLC AP hastransitioned to a power-on state, and wherein disabling operation of thesecond VLC AP and the third VLC AP to communicate with UEs comprises:communicating toward the second VLC AP a message containing a power-offcommand; and communicating toward the third VLC AP a message containinga power-off command.
 4. The method of claim 2, wherein disablingoperation of the second VLC AP and the third VLC AP to communicate withUEs comprises: responsive to determining that the second VLC AP and thethird VLC AP each have communication coverage area of the first VLC AP,initiating re-routing of data packets, which are addressed to a UEwithin the communication coverage area of the second VLC AP, to bedirected to the first VLC AP instead of to the second VLC AP; andresponsive to determining that the second VLC AP and the third VLC APeach have communication coverage area of the first VLC AP, initiatingre-routing of data packets, which are addressed to another UE within thecommunication coverage area of the third VLC AP, to be directed to thefirst VLC AP instead of to the third VLC AP.
 5. The method of claim 2,further comprising: identifying loss of ability of the first VLC AP tocommunicate with UEs; and responsive to identifying the loss of abilityof the first VLC AP, controlling the second VLC AP and the third VLC APto restore their operations to communicate with UEs.
 6. The method ofclaim 1, wherein identifying the occurrence of the event relating tooperation of the first VLC AP comprises identifying transition of thefirst VLC AP to a power-on state ready for communications with UEs, andwherein controlling the second VLC AP and the third VLC AP comprisescontrolling the second VLC AP and the third VLC AP to prevent use of atleast one light frequency band for VLC that is to be used by the firstVLC AP for VLC with UEs subsequent to the occurrence of the event. 7.The method of claim 1, wherein determining that the second VLC AP andthe third VLC AP each have communication coverage areas that are atleast partially within the communication coverage area of the first VLCAP comprises accessing a coverage area topology repository using anidentifier for the first VLC AP to obtain an identifier for the secondVLC AP and an identifier for the third VLC AP, and wherein the coveragearea topology repository maps identifiers for minor VLC APs toidentifiers for major VLC APs that at least partially overlap smallercommunication coverage areas of the mapped ones of the minor VLC APs. 8.The method of claim 1, further comprising: determining a confidentialitylevel of information contained in packets being communicated to UEs;selecting between using the first VLC AP or using the second VLC AP andthe third VLC AP to communicate with the UEs based on the determinedconfidentiality level of information; and responsive to selectingbetween using the first VLC AP or using the second VLC AP and the thirdVLC AP, controlling the first VLC AP, the second VLC AP, and the thirdVLC AP.
 9. The method of claim 1, further comprising: determiningcommunication bandwidth utilization of the VLC APs communicating withUEs; selecting between using the first VLC AP or using the second VLC APand the third VLC AP to communicate with the UEs based on thecommunication bandwidth utilization; and responsive to selecting betweenusing the first VLC AP or using the second VLC AP and the third VLC AP,controlling the first VLC AP, the second VLC AP, and the third VLC AP.10. The method of claim 1, further comprising: determining communicationcapabilities of receiver circuits included in the VLC APs; selectingbetween using the first VLC AP or using the second VLC AP and the thirdVLC AP to communicate with the UEs based on the communicationcapabilities; and responsive to selecting between using the first VLC APor using the second VLC AP and the third VLC AP, controlling the firstVLC AP, the second VLC AP, and the third VLC AP.
 11. The method of claim1, wherein identifying the occurrence of the event relating to operationof the first VLC AP comprises identifying the occurrence of the eventduring communication between the first VLC AP and a UE within the commoncommunication coverage areas of the second VLC AP or the third VLC AP.12. A coordination node for controlling communications between VisibleLight Communication, VLC, Access Points, APs, and user equipments, UEs,the coordination node comprising: a network interface; a processorcoupled to the network interface; and a memory coupled to the processorand storing program code that when executed by the processor causes theprocessor to perform operations comprising: identifying occurrence of anevent relating to operation of a first VLC AP; responsive to identifyingthe occurrence of the event, determining that a second VLC AP has acommunication coverage area that is at least partially within acommunication coverage area of the first VLC AP; and responsive todetermining that the second VLC AP has a communication coverage areathat is at least partially within a communication coverage area of thefirst VLC AP, controlling the second VLC AP, separate from handling overa UE between the first VLC AP and the second VLC AP, to avoid the secondVLC AP from interfering with communications between the first VLC AP andany UEs within a common communication coverage area of the second VLC APand the first VLC AP.
 13. The coordination node of claim 12, whereinidentifying the occurrence of the event relating to operation of thefirst VLC AP comprises identifying that the first VLC AP has becomeoperational to communicate with UEs located within at least part of thecommunication coverage area of the second VLC AP, and whereincontrolling the second VLC AP comprises disabling operation of thesecond VLC AP to communicate with UEs.
 14. The coordination node ofclaim 13, wherein identifying that the first VLC AP has now becomeoperational to communicate with UEs located within the communicationcoverage areas of the second VLC AP comprises identifying that the firstVLC AP has transitioned to a power-on state, and wherein disablingoperation of the second VLC AP to communicate with UEs comprisescommunicating toward the second VLC AP a message containing a power-offcommand.
 15. The coordination node of claim 13, wherein disablingoperation of the second VLC AP to communicate with UEs comprises:responsive to determining that the second VLC AP has a commoncommunication coverage area of the first VLC AP, initiating re-routingof data packets, which are addressed to a UE within the communicationcoverage area of the second VLC AP, to be directed to the first VLC APinstead of to the second VLC AP.
 16. The coordination node of claim 13,wherein the operations further comprise: identifying loss of ability ofthe first VLC AP to communicate with UEs; and responsive to identifyingthe loss of ability of the first VLC AP, controlling the second VLC APto restore their operations to communicate with UEs.
 17. Thecoordination node of claim 12, wherein identifying the occurrence of theevent relating to operation of the first VLC AP comprises identifyingtransition of the first VLC AP to a power-on state ready forcommunications with UEs, and wherein controlling the second VLC APcomprises controlling the second VLC AP to prevent use of at least onelight frequency band for VLC that is to be used by the first VLC AP forVLC with UEs subsequent to the occurrence of the event.
 18. Thecoordination node of claim 12, wherein determining that the second VLCAP has a communication coverage area that is at least partially withinthe communication coverage area of the first VLC AP comprises accessinga coverage area topology repository using an identifier for the firstVLC AP to obtain an identifier for the second VLC AP, and wherein thecoverage area topology repository maps identifiers for minor VLC APs toidentifiers for major VLC APs that at least partially overlap smallercommunication coverage areas of the mapped ones of the minor VLC APs.19. The coordination node of claim 12, wherein the operations furthercomprise: determining at least one of: a confidentiality level ofinformation contained in packets being communicated to UEs, acommunication bandwidth utilization of the VLC APs communicating withUEs, and communication capabilities of receiver circuits included in theVLC APs; selecting between using the first VLC AP or using the secondVLC AP to communicate with the UEs based on at least one of: thedetermined confidentiality level of information, the communicationbandwidth utilization of the VLC APs communicating with UEs, and thecommunication capabilities of receiver circuits included in the VLC APs;and responsive to selecting between using the first VLC AP or using thesecond VLC AP, controlling the first VLC AP and the second VLC AP.
 20. Anon-transitory computer-readable having instructions stored therein thatare executable by a coordination node to perform operations forcontrolling communications between Visible Light Communication, VLC,Access Points, APs, and user equipments, UEs, the operations comprising:identifying occurrence of an event relating to operation of a first VLCAP; responsive to identifying the occurrence of the event, determiningthat a second VLC AP and a third VLC AP each have communication coverageareas that are at least partially within a communication coverage areaof the first VLC AP; and responsive to identifying the occurrence of theevent, controlling the second VLC AP to avoid it interfering withcommunications between the first VLC AP and a UE while it is within acommon communication coverage area of the first VLC AP and the secondVLC AP; and responsive to identifying the occurrence of the event,controlling the third VLC AP to avoid it interfering with communicationsbetween the first VLC AP and the UE while it is within a commoncommunication coverage area of the first VLC AP and the second VLC AP.